Update sample .yaml to give noobs (like me) an easier starting point (#22629)

source/_integrations/systemmonitor.markdown

@@ -141,3 +141,44 @@ Wireless LAN adapter Wireless Network Connection:
 ```
 
 Where the name is `Wireless Network Connection`.
+
+## All available resources
+
+```yaml
+# Example configuration.yaml entry with all entry types (delete/comment out as necessary)
+sensor:
+  - platform: systemmonitor
+    resources:
+      - type: disk_use_percent
+        arg: /config
+      - type: disk_use
+      - type: disk_free
+      - type: memory_use_percent
+      - type: memory_use
+      - type: memory_free
+      - type: swap_use_percent
+      - type: swap_use
+      - type: swap_free
+      - type: load_1m
+      - type: load_5m
+      - type: load_15m
+      - type: network_in
+        arg: eth0
+      - type: network_out
+        arg: eth0
+      - type: throughput_network_in
+        arg: eth0
+      - type: throughput_network_out
+        arg: eth0
+      - type: packets_in
+        arg: eth0
+      - type: packets_out
+        arg: eth0
+      - type: ipv4_address
+        arg: eth0
+      - type: ipv6_address
+        arg: eth0
+      - type: processor_use
+      - type: processor_temperature
+      - type: last_boot
+```